Answer to Diagnostic Challenge

1. Wang CL , Shieh JY , Wang TG , Hsieh FJ : Sonographic detection of occult fractures in the foot and ankle. J Clin Ultrasound 1999;27(8):421-425.

2. Rizzatto G , Abbona M , Mininel G : Bone and callus, in Solbiati L , Rizzatto G (eds), Ultrasound of Superficial Structures: High frequencies, Doppler and interventional procedures. Edinburgh: Churchill Livingstone, 1995, pp 375-382.